Theoretically, the promotion of "small portion" and "half portion" will not increase the cost of time, manpower and material resources, but may have the following benefits:

1. Reduce waste: Providing "small dishes" and "half dishes" can provide appropriate food according to the needs of guests, reduce waste and help protect the environment.

2. Improve customer satisfaction: Providing different portions of food allows customers to choose the amount of food they need more flexibly and improve customer satisfaction.

3. Increase sales: By providing "side dishes" and "half dishes", we can attract more customers with low consumption but diverse choices, thus increasing sales.

Of course, the actual situation still needs to consider some factors, such as the cost of small dishes, supply chain coordination, food research and development and so on. If these factors are properly planned and managed, promoting small portions and half portions can reduce waste and improve sales and customer satisfaction.